Patent GB-868757-A (GB)
Title: Improvements in or relating to calculating machines
Inventor: KITZ NORBERT
IPC: G06F7/52
Filed: 1956-09-06
Abstract: 868,757. Digital electric calculating-apparatus. BELL PUNCH CO. Ltd. Sept. 2, 1957 [Sept. 6, 1956; Nov. 26, 1956; July 3, 1957], Nos. 27566/57, 27567/57 and 27568/57. Divided out of 868,753. Class 106 (1) The calculating machine described in Specification 868,753, is provided with means for effecting multiplication by a multi-digit multiplier. Shift.-Means are provided for transferring the contents of each counting tube into the counting tube of next higher order by adding pulses into each order sufficient to produce a transfer from that order whereupon the remaining pulses from a total of ten pulses are added into the counting device of next higher order. The machine is provided with two additional sets of contacts O 12 -O 21  &c. and O 22 -O 30  &c. and an associated pair of valves adapted to apply potential alternatively to one of the two sets, each batch of contacts of one set being associated with a commutator segment of a particular order of keys, and each batch of contacts of the other set being associated with the commutator segment of the next adjacent order of keys. A brush F<SP>1</SP> rotates together with the brush F, and with switches CS 3 , CS 4 , CS 5 , CS 7 , CS 8 , CS 9  set for multiplication, actuation of a multiplifier key causes a pulse from a condenser U 4  via electrodes E to cause a valve T 6  to conduct, rendering an associated valve T 5  non-conducting thereby placing zero potential on electrodes E‹ associated with commutator segments Z 9 -O 9  which thus enables zero potential to be applied via the brush F<SP>1</SP> and electrodes E associated with contacts O 12 -O 21  &c. to render a valve T 8  conductive to apply a potential to the contacts O 12 -O 21  &c. The first transfer impulse to be emitted is from the counting tube O 10  and this impulse is passed via a gate G 5  to render the valve T 7  conductive thus applying a potential to the contacts O 22 -O 30  &c., the subsequent bridging of the contacts F‹-F‹ sending a positive impulse to the cathodes of the valves T 7  and T 8  to render the valve T 7  non-conducting. If the counting tube O 10  originally had a digit registered therein, the tube will pass through zero during the reception of the ten pulses, thereby energizing the electrodes O 22 - O 30  at such a time that a number of pulses pass via the brush F<SP>1</SP> to cause the digit to be registered in the counter of next higher order. In this way any number registered in the counting tubes is effectively multiplied by ten. Multiplication.-The machine is first set for multiplication and the multiplicand is entered into the keyboard. The highest multiplier digit is then set up in the counting tube L by depression of the appropriate key in a column of multiplier keys. The brush F<SP>1</SP> then commences to rotate and results in ten pulses being supplied to each counting tube, the tubes being left registering zero. During subsequent cycles of the brushes, the multiplicand is added into the counting devices a number of times equal to the multiplier digit. The next multiplier digit is now entered in the multiplier keys, an effective shift operation taking place before fresh additions of the multiplicand occur. Keyboard, Fig. 3. On actuation of the multiplication key 39, a stirrup 43 is rocked to draw a switch rod 41 into the path of a flap thereby preventing engagement of the motor contacts when the multiplicand is inserted. Subsequent actuation of a multiplier key of the column 38 causes a bar 48 to withdraw the rod 31 to permit the motor contacts to engage. On depression of the multiplication key 39, a link 59 is moved to the right to cause a member 54 to move clockwise thereby disengaging the pulley 51 from the dog 53 thus disconnecting the drive to the shaft 50. When the multiplication key has been latched down for a series of multiplications, the actuation of " cancel" keys 89, 90 or " display " keys 91, 92 rocks a stirrup 65 to move the link 59 to the left thus re-engaging the drive of the shaft 50. The multiplication key may be latched temporarily or permanently by depression and rocking forwards or backwards (Fig. 12, not shown), and the division and subtraction keys may be latched temporarily. Specifications 868,756, 868,758, 868,759, 868,760 and 868,761 are referred to.